1. Field of the Invention
The present invention relates to a semiconductor structure, and more particularly, to a semiconductor capacitor structure.
2. Description of the Prior Art
In modern integrated circuits (ICs), capacitors are prevalently used to achieve different functions such as dynamic random access memories, bypassing, and filters. In typical analog IC processes, the capacitors are constructed by sandwiching a dielectric material between two conductive materials. For example, the capacitors usually used in the art include the metal-insulator-metal (MIM) capacitor and the metal-oxide-metal (MOM) capacitor.
Capacitances of the capacitors are very sensitive to the fabrication process and structure design. Accordingly, a variance of capacitance caused by misalignment is always unwanted. Therefore it is desirous to reduce variation in the structure and obtain a higher capacitance for the semiconductor capacitors.